Paper-making machine.



No. 733.709; EAIBNTED JULY 14, 1903.

0. M. FLRWBL-l, PAPER MAKING APPLIOAHGIS; E'ILBJL Mizax.. ze, 1.1mm

lo MODEL.

N@ D @e 'mi e/LU e: p l 1w r.' ,Ma www UNITED STATES Patented July 14, 1903.

PATENT OFFICE.

OTIS M. FARWELL, OF KAUKAUNA, WISCONSIN, ASSIGNOR TO THILMANY PULP St PAPER COMPANY, OF' KAUKAUNA, IVISCONSIN, A CORPORA- TION OF W'ISCONSIN.

PAPER-MAKING MACHINE.

SPECIFICATION forming part of Letters Patent No. 733,709, dated July 14, 1903.

Application filed August 20, 1902. Serial No. 120,289. (No model.)

:To @ZZ whom it may concern.-

Beit known that I, OTIS M. FARWELL,a citizen of the United States,and a resident of Kaukauna, in the county of Outagamie, State of Wisconsin, have invented certain new and useful Improvements in Paper-Making Machines, of which the following is a full, clear, and exact description.

This invention has for its object to so iinprove paper-making machines of the continuous-web type that the watermarking of the paper may be more effectively accomplished than has heretofore been4 possible, particularly with long-fiber tissue or like thin paper.

In paper-making machines the common practice is to effect the watermarking of paper by placing between the suction-boxes of the machine a dandy-roll, by which the desired water-marks are impressed upon the pulp. Such practice has been found unsatisfactory, and particularly so for the marking of long-fiber stock, such as thin long-fiber tissue or the like, for the reason that after the water-marks have been impressed upon the paper by the dandy-roll at the location indicated the paper web passes through the couch-rolls, the press-rolls, and on to the drying-cylinder, and the water-mark becomes more or less obliterated. Indeed, it has been found practically impossible to satisfactorily mark thin tissue or paper of long-fiber stock in a continuous-web machine with the dandyroll so located. It has also been heretofore proposed to effect the watermarking of the paper web at various points between the couch-rolls and the calenders, and different kinds of impression-surfaces have been heretofore suggested for impressing the web of paper with the desired marks. The most practical and effective means for impressing the paper web with the desired marks is a type-carrying cylinder, and the most effective point at which to locate this type-carrying cylinder is opposite the web-drying cylinder of the machine, since as the web passes around the drying-cylinder it is sufficiently damp to permit the type to compress or compact the paper between it and the surface of the cylinder, while the continued passage of the paper web around the cylinder after having received the type impressions insures the fixing or baking, as it may be termed, of the impressions into the paper before it leaves the cylinder. The result is that the forcible compression of the ber of the paper web renders those parts thus subjected tothe markingtype comparatively dark and distinct even after the web has passed through the calender-rolls. Various objections, however, are found to exist to marking the paper web direct from the type or impression-surface. In the first place the drying cylinders or rolls are necessarily subjected to various degrees of heat, according to the character of the paper passing over the1n,and consequently these cylinders or rolls contract and expand differently, thus creating more or less unevenness of surface, particularly if the drying cylinders or rolls be very long. Again, although the drying cylinders or rolls be turned as accurately as possible with a lathe the entire surface of the cylinder or roll will not be so mechanically true but that slight variations will occur between it and any type-carrying roll coperating therewith to effect the marking of the paper web, since slight inaccuracies or irregularities between the impressionsurface of the marking-roll and the surface of the drying cylinder or roll are certain to eX- ist. Moreover, when the impression-surface of the marking-roll acts directly against theV surface of the paper web on the drying-cylinder the slightest inaccuracies or irregularities that may exist between the impressionsurface and the drying-cylinder will permit a slight slipping or inequality of lineal movement that tends to cause the type-faces to tear or strain the paper web, and as the face of the type or impression-surface becomes worn the difficulties above mentioned are necessarily exaggerated. Y

Ihave discovered (and herein my invention broadly resides) that by interposing a sheet of suitable fabric between the impression-surface and the paper web a far more uniform and effective marking of the web may be accomplished than is possible where the marking of the web is made direct from the impressionsurface or type, and by this means the marking of both long and short fiber stock, but

IOO

particularly the former, may be more effect- -ively accomplished. Preferably in carrying out my invention the marking of the paper web is effected at a point opposite the drying cylinder or roll, so that the impression-surface acts upon the web after it has been partially dried, but while it is yet in condition to allow the compression of the fiber at points opposite the impression-surface, and yet insure the fixing or baking of the marks into the web before it leaves the drying-cylinder; but while such is the preferred location of the marking device still without departure from the broad scope of my invention it will be understood that the marking of the paper web in keeping with the invention may be effected at other points after the web has left the couch-rolls.

The drawing illustrates a diagram matic view, in side elevation, of one form of papermaking machine embodying my invention, although it will be understood that the invention is applicable to other types of paper-making machines.

The machine frame may be of ordinary type.

B denotes the endless wire-cloth, that is supported by rollers a in the usual manner and passes over the top of the machine and above the suction-boxes C.

D and D denote the couch-rolls, around the lower one D of which the wire-cloth B passes.

E designates the lower and F the upper blanket-felt. The lower blanket-felt E passes around the rolls c e', duc., and over the lower press-roll G, while the upper blanket-felt F passes around the rolls ff, uc., and beneath the upper press-roll G and the pressure-roll H and idler-roll f5, these last two rolls forcing the upper blanket-felt F toward the drying-cylinder K. Beneath the upper blanket felt or fabric F and jonrnaled in suitable spring-bearings, (not shown,) which force it toward the drying-cylinder K, is mounted the marking-roll M. As shown, this marking-roll cooperates With the pressure-roll H in forcing the upper blanket-felt F toward the periphery of the drying-cylinder K. The marking-roll M will carry the impression-surface whereby the desired marking of the paperweb will be effected, and preferably this impression-surface will be raised from the periphery of the roll M. 'From the roll M the paper is carried up over the drying-cylinder K in usual manner and thence through and out of the machine. By interposing a sheet of fabric-such, for example, as blanketfelt-between the impression-surface and the web of paper a most effective and uniform marking of the web is accomplished, notwithstanding the unavoidable irregularities and inaccuracies in the surface of the drying-cylinder and of the impression-surface. Moreover, the wear upon the impression-surface is obviated, and all danger of tearing the paper web is avoided. It is obvious that the precise details of construction above set out may be varied in wide limits without departure from the spirit of the invention.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is-

l. In a paper-making machine, the combination with a marking-roll carrying an impression-surface for marking the web of paper, of a sheet of fabric interposed between said impression-surface andthe paper web.

2. In a paper-making machine, comprising couch-rolls press-rolls and a drying cylinder or roll, the combination with said drying cylinder or roll, of the marking-roll and a sheet of fabric interposed between said markingroll and the surface of the web of paper.

3. In a paper-making machine comprising suitable suction-boxes, couch-rolls, pressrolls, blanket-felt and drying-cylinder, a marking-roll having an impression-surface and arranged adjacent the drying-cylinder and serving to impress the paper Web through the blanket-felt and against said cylinder.

OTIS M. FARWELL.

Witnesses:

CHARLES W. STRIBLEY, MARION D. RowLANp. 

